The posterior tibialis muscle is a major stabilizer of the medial foot, decelerates pronation, and exhibits constant EMG activation from initial ground contact through propulsion.

“posterior tibialis decelerates pronation mhm it has to be and you know fun fact if you look at EMG activity and call it what you will some people don't love EMG activity um just because there's a lot of a crossover y but posterior tib you will see activation from that guy from the second of foot's on the ground until propulsion he's one of the only tissues muscles where you'll see this constant activation”